Fluid displacement rotary machine



June 5, 1951 Filed June 9, 1949 R. E. CORNWELL FLUID DISPLACEMENT ROTARYMACHINE 3 Sheets-Sheet l JNVENTOR. R LPH E. C o/e/v WELL BY 9W w 1 A TTORNEY June 5, 1951 -R. E. CORNWELL FLUID DISPLACEMENT ROTARY MACHINE 3Sheets-Sheet 2 Filed June 9, 1949' RALPH E. COR/v WIDELL ATTORNE Y June5, 1951 Fil ed June 9, 1949 R. E. CORNWELL.

FLUID DISPLACEMENT ROTARY MACHINE 3 Sheets-Sheet 3 /4 /a {it INVENTOR.P/uPH E. [ORNWELL BY gmokw ATTORNEY Patented June 5, 1951 UNI T ES PATENT F E [C 2,555,679.-

FLUIDY DISPLACEMENT ROTARY MACHINE Ralph: E. amen, La Canada, Calif.

Application Jime 9, 1949, Serial-No. 97,956I

My present invention relatesxto hydraulic driving, braking and freewheeling mechanisms of the general character embodied inmy: UnitedStates Letters PatentNo. 234211013; issued to me on MayZ'i, 1947.

In my patent above identified; the mechanism includes hydraulic pumpsoperatively connected to wheel motors and to the prime mover of thevehicle to deliver power tothe whe'el motors with a minimum of hydraulicfrietionloss'es'; to impose any degree of braking action uponthe wheelsthrough the medium of the'whcel motors'; to'enable freewheel operationof the vehicle to be effected with a minimum of fluid drag; and tocentrol the-fiow of hydraulicenergybyvalving partitions of'the pumpsand'wheel' motors in a manner to vary the volume of'fl'uid circulatedtherebetween, to accordingly vary the hydraulic energy at the wheelmotors fordriving andbrali ing purposes, or tocause the circulation ofthe fiuididly-within the pumps and wheel motors-for free wheelingoperation of the latter.

An object of my present invention is to provide afluid displacementmechanism having the aforestated advantages of? my patented mecha ni'sm;and structurally characterized by novel stator and rotor structuresco-acting to define=a highly efficient fluid seaIed annular workingchamber which is relatively deep in a. direction radially of the rotor,for co-action with vanes oi -longitudinally curved contour, try-minimizemechanical and fluid friction and to obtain a smoother fluid flow formaximum hydraulic cfficiency, with the vanes being" slidably mounted inthe rotor in a manner to materially'r-educ'e the centrifugally causedmechanical friction of the vanes against'the Wall of' the stator,toth'ereby reduce the adverse effect of centrifugal force acting uponthe vanestoretardrotation of'the rotor, whereby to increase theefficiency of the mechanism as compared to mechanisms heretoforeproposed and embodying flatvanes of the type which are slidably mountedin therotor'for movement radially thereof.

Another object of this invention i'sto-provide a; fluid displacementmechanism oithe above described character in which the vanes embodymeans to deliver to the dischargesideof the machine, such fluid as mightleak from the-working chamber into stator spaces or chambers at oppositesides of the rotor, to thereby maintain maximum volumetric efficiency;

A further object of this invention is to provide means by which thevanescan be moved to an idle positionclear of the working chamberfor freewheeling or idling operation, as well'as for testing purposes.

With these and other objects in- View, myiin vention resides in thecombinations, arrangements and functional relationships of elements asset forth in the following and particularly pointed out in the appendedclaims.

In the accompanying drawings,

Figure 1 is'a view in side elevation, of one form of fluid displacementrotary machine embodying my present invention, with a portion of onestator section broken away todisclose rotor and vane structure;

Figure 2 is an enlarged axial sectional view taken entire line 22' ofFigure 1';

Figure 3 is a transverse sectional view taken onthe line 3-3of Figure 2Figure' l is a detail sectional view taken on the line 4-4 of Figure 2;v

Figure 5 is a perspective view of one of the vanes embodied in theinvention; and

Figurefi is a fragmentary sectional View taken on the line 6-6 of Figure3.

Referring specifically to the drawings, my invention in its illustratedembodiment will be described as a wheel motor, although its use as apump or as either in other environments is to be considered as' withinthe scope of this. disclosure. The hydraulicmotor designated, generallyby M, is broadly composedof a.,fixed casing or stator S,,a disk rotor R,vanes V, a valving partition P; and a controldevice D for the vanes;

The stator S comprises a body section l0. hav ing. a bearing l l, and acover section II having a bearing [3 and being secured to the bodysection by bolts [4,,to define within thesections a cylindrical space orchamber l5 communicating at adjacent locations on its periphery with aninlet conduit i5 and: an outlet conduit ll. controlled by the interposedvalving, partitionP.

Ehe rotor R has arunning fit circumferentially in the stator chamberl5,- and is fixed to awheelhub or other, driven-element 18 by a key l9,which hub is rotatably mountedonthewheel spindle orqaxle 2D; The axialdimension of; the rotor' R is considerably less than; that; of thestator chamber l5", and is located medially of: the latter so as toleave on the outer sides of the rotor; cylindrical lateral portionsI511; oi the chamber l5. The-circularcontinuity-of the chamber portionsI5'a is interrupted?symmetrically of the valvingpartition P by identicalcams-:21, Zi whose ends" merge smoothly into the peripheries 3 of therespective portions |5a as shown in broken lines in Figures 1 and 3.

The sides of the rotor R have a running fit between the confrontingsides of the cams 2|, 2|, and the rotor is provided with a peripheral,annular recess relatively deep in a direction radially of the rotor andopening to th internal annular surface of the stator chamber.| 5 forco-action with same in defining a working chamber 25 which slidablyreceives the valving partition P in the extreme position shown inFigures 2 and 3, wherein the partition is completely effective tointerrupt the-working chamber 25 between the inlet conduit l6 and theoutlet conduit II, for

driving of the rotor, and as clearly shown in full lines in Figure 3.

By means (not shown) forming no part per se of the present invention,the valving partition P can be moved to its other extreme position shownin broken lines in Figure 3, to completely close off the conduits I6 andI! from the working chamber 25 and clear the latter for free wheelingoperation. In various intermediate positions of the partition P, theconduits I6 and I1 will be restricted to a greater or lesser extentaccording as more or less braking operation is to be effected.

The vanes V, of which four are shown for the purpose of illustration,are curved or segmental in longitudinal contour, and are of such widthor dimension axially of the rotor as to have a running fit against thesides of the stator chamber I5. These vanes are slidably mounted incorrespondingly curved slots 30 formed in the rotor R at equally spacedlocations circumferentially thereof. The outer ends of the vanes areprovided with slots 3|, 3|, (Figure 5) of such width as to slidablyreceive the flanges 32, 32 of the rotor which form the sides of theworking chamber 25. Thus, the central tip portion 33 of each vane willoperate in the working chamber, whereas the lateral portions 34 of thevane will operate in the lateral portions |5a of the stator chamber l5,for engagement with the cams 2| in moving the respective vanes inwardlyof the working chamber 25 to an extreme retracted position wherein thevanes will clear the valving partition P when the latter occupies itsextreme position spanning the working chamber, as clearly shown inFigures 2 and 3.

Ducts 35 and 36 in the stator sections l and I2, respectively, place theportions |a of the stator chamber l5 in communication with the outletconduit so that any fluid which may leak from the working chamber 25into the stator chamber IE will be discharged from the latter into theducts 35 and 36 and thence into the outlet conduit by the lateral tipportions 34 of the vanes V during rotation of the rotor R in thedirection of the arrows in Figure 3. Springurged check valves 31 and 38are mountedin the respective ducts 35 and 36 and operate to prevent anyreverse flow of liquid from the outlet conduit into the stator chamberl5.

The control device D comprises a sleeve 40 rotatable and axiallyshiftable on the hub l8 and having teeth on its forward or inner end toprovide a crown gear 4|. Each of the vanes V is provided along one sideedge with teeth to form a segmental gear 42 with which the crown gear 4|is adapted to be meshed. A shifting fork 43 pivoted at 44 on a fixedbracket 45, is provided with pins 46 working in an annular groove 41 inthe sleeve 40, for co-action with such groove in axially shifting thesleeve 40 from, one extreme position to another according as the crowngear 4| is to be meshed with or unmeshed from the segmental gears 42 ofthe vanesV. A thumb screw 48 passing freely through an opening in thefork 43, is adapted to be screwed into either of two threaded bores 49and 50 in the bracket 45 to accordingly lock the fork in one or theother of its aforesaid extreme positions.

The sleeve 40 is provided with an actuating and locking screw 55 havinga head 56 and being threaded into a radial bore 51 in the sleeve. Theinner end of the screw 55 is reduced in diameter to form a locking pin58. With the sleeve 40 shifted on the hub l8 to its advanced position 7wherein the gear 4| will be meshed with the segmental gears 42 of thevanes V, rotation of the sleeve in a counterclockwise direction asviewed,

in Figure 4, by using the screw head 56 as an actuator for the sleeve,will cause the gears 4| and 42 to co-act in retracting the vanes V toclear their outer ends from the working chamber 25 for free wheeling andtesting operations.

The maximum amount of rotational movement of the sleeve 40 necessary tothus retract the vanes, is positively limited by a pin 59 in the sleeve,working in an arcuate slot 60 in the hub l8. In this rotationallyadjusted position of the sleeve 4|] on the hub I8, the locking screwwill be co-axially related to a recess 6! in the hub, so that by nowfurther screwing the screw 55 into the sleeve 40, the pin 58 of thescrew will enter the recess 6| to lock the sleeve to the hub againstrotation thereon, and thus lock the vanes in retracted position.

The operation of the invention is-as-followst-- Let it be assumed thatthe outlet conduit l1 and the inlet conduit l6 are respectivelyconnected to the intake and discharge sides of a pump (not shown) suchas is disclosed in my patent above referred to, and that the fluidcircuit between such pump and motor M is completely filled with liquid.

With the valving partition P occupying the position shown in full linesin Figure 3; the vanes V advanced as also shown in this figure; and thepump in operation, liquid from the pump entering the working chamber 25through the inlet conduit |6 will act upon the vanes V in succes siveorder to rotate the rotor R in the counterclockwise direction shown bythe arrows in this figure. It will be noted that in view of thelongitudinally curved contour of the vanes V and the disposition of therotor slots 30 in which the vanes are mounted, the centrifugally causedfriction of the tips'of, the vanes against the wall of the statorchamber l5 and the cams 2| is materially reduced, as a portion of thecentrifugal force act.- ing upon the vanes, urges the vanes laterallyagainst the walls of the rotor slots 30, thus reducing the wear upon thevane tips and stator wall surfaces as well as rendering the vanes easierto retract, all while insuring that a sufficient amount of thecentrifugal force will effectively urge the vanesto their advancedpositions in con- 7 able a radially deeper working chamber to beutilized in the rotor, with the attending advantages of smoother fluidflow and less fluid friction, so as to provide greater hydraulicefficiency. Also, the curved vanes, freely movable in the rotor slotsand retractable by the cams 2|, reduce to a minimum the number of partsrequired, and thus reduce the cost of manufacture while attaining moremechanical efficiency and higher rotor speeds.

I claim:

1. A fluid displacement rotary machine comprisingz ja stator; a rotorrotatably mounted in the stator and co-acting therewith to define anannular working chamber therebetween; said stator having juxtaposedinlet and outlet ports communicating with said working chamber at theperiphery thereof; a valving element mounted in the statorbetween saidports for movement from a position in said working chamber to a positionclear of the latter; a plurality of curved vanes; said rotor havingcurved slots in which said vanes are slidably mounted, so that when therotor is rotating, the vanes will be urged at their ends against theperimeter of the working chamber by only a portion of the centrifugalforce acting upon the vanes, whereas the remainder of the actingcentrifugal force will urge the vanes laterally against the walls ofsaid slots so as to minimize the mechanical friction between the vaneends and the stator; means co-acting with the vanes during rotation ofthe rotor, to retract the vanes at the location of said valving elementso as to enable the vanes to pass said element when-occupying a positionin the working chamber; said vanes having gear teeth along a side edgethereof; a gear mounted co-axially of said rotor for rotation and axialmovements; means by which said gear can be axially moved to engage saidvane teeth; and means by which said gear can be rotated to co-act withsaid vane teeth in retracting the vanes clear of the working chamber fortesting and idling operations.

2. A fluid displacement rotary machine comprising: a stator having acylindrical chamber; a rotor rotatably mounted in said chamber coaxiallythereof, with the sides of the rotor spaced from the sides of saidchamber and the periphery of the rotor having a running fit in saidstator chamber for co-action with the annular surface of the latter indefining an annular working chamber between stator and rotor; saidstator having juxtaposed inlet and outlet ports communicating with saidworking chamber at the periphery thereof; a valving element mounted inthe stator between said ports for movement from a position in saidworking chamber to a position clear of the latter; a plurality of curvedvanes mounted in said rotor to project from opposite sides thereof intosaid stator chamber and adapted to be urged by centrifugal force intosaid working chamber and against said annular surface of said statorchamber when the rotor is rotating; means in said stator chamber atopposite sides of the rotor, co-acting with said projecting portions ofthe vanes during rotation of the rotor, to retract the vanes at thelocation of said valving element, so as to enable the vanes to pass saidelement when the latter occupy a position in the working chamber; saidstator having check valve-controlled conduits in communication with saidstator chamber and said outlet port, into which fluid leaking from theworking chamber into'said stator chamber will be discharged by saidprojecting portions of the vanes so as to be delivered to said outletport; said vanes having gear teeth along a side edge thereof in saidstator chamber; a gear mounted co-axially of saidrotor for rotation andaxial movements; means by which said gear can be axially moved into saidstator chamber to engage said vane teeth; and means by which said gear'can be rotated to co-act with said vane teeth in retracting the vanesclear of the working chamber for testing and idling operations.

RALPH E. CORNWELL.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 380,489 Jefieris Apr, 3, 1888392,356 Minier Nov. 6, 1888 471,279 Taber Mar. 22, 1892 1,320,892 MunnNov. 4, 1919 1,831,243 Hart Nov. 10, 1931 2,178,405 Reggio Oct. 31, 19392,260,809 Johnson Oct. 28, 1941 2,281,157 Kanuch Apr. 28, 1942 2, 21,013Cornwell May 27, 1947 2,460,251 Diaz" Jan. 25, 1949 2,477,371 HartzlerJuly 26, 1949 FOREIGN PATENTS Number Country Date 381,371 Great BritainOct. 6, 1932

